Another interesting read about pixel here: <a href="https://medium.com/@brucewangsg/the-story-of-pixel-density-and-touch-interface-afd97e8f78fc" rel="nofollow">https://medium.com/@brucewangsg/the-story-of-pixel-density-a...</a>
A pixel is not a little square...<p><a href="http://alvyray.com/Memos/CG/Microsoft/6_pixel.pdf" rel="nofollow">http://alvyray.com/Memos/CG/Microsoft/6_pixel.pdf</a>